Control traffic is often used to advertise routes and/or node-identity information (such as Internet Protocol (IP) addresses, Media Access Control (MAC) addresses, and/or link-layer addresses) among network nodes within a network. For example, a network node may send a neighbor solicitation to various neighbors of the network node that are all connected to the same link. The neighbor solicitation may effectively query these neighbors for their respective IP and/or link-layer addresses.
In response to the neighbor solicitation, these neighbors may each send a neighbor advertisement back to the network node. These neighbor advertisements may identify and/or include the IP and/or link-layer addresses of the solicited neighbors. Upon receiving these neighbor advertisements, the network node may record the IP and/or link-layer addresses of the solicited neighbors in a neighbor cache that includes entries for neighbors of the network node. This network node may then refer to and/or rely on these entries in the neighbor cache to forward traffic to the corresponding neighbors.
These entries may each have a status that indicates whether the corresponding neighbor is currently known to be reachable via that link. In a traditional configuration, to maintain a neighbor cache entry in a reachable state, the network node may either glean hints of the corresponding neighbor's reachability from Transmission Control Protocol (TCP) traffic or perform a reachability confirmation using the Neighbor Discovery (ND) protocol. Since ND reachability confirmations often generate a lot of control traffic within the network, the process of gleaning hints from TCP traffic may be preferable and/or advantageous.
Unfortunately, some network nodes may experience lulls in TCP traffic. As a result, in the traditional configuration, these network nodes may need to perform reachability confirmations using the ND protocol to determine whether certain neighbors are still reachable, thereby generating significant amounts of control traffic within the network and/or consuming network resources and/or bandwidth. The instant disclosure, therefore, identifies and addresses a need for methods, systems, and apparatuses for reducing control traffic in connection with neighbor reachability confirmations.